Federal prosecutors in Manhattan announced yesterday that seven employees of the United States Immigration and Naturalization Service and 26 others had been charged with selling fraudulent immigration papers for more than $100,000 in bribes.

The case, the third similar scheme in recent years, continues to raise questions about how well the agency is addressing its vulnerability to corruption. The scheme grew so brazen, prosecutors said, that some cash bribes were exchanged right inside the I.N.S. offices at 26 Federal Plaza in downtown Manhattan.

The immigration employees accused in the case included five officers who interview immigrants and have the power to approve applications for green cards, which confer permanent legal status as a United States resident and are granted only in limited circumstances. Two lower-level employees were also arrested.

Others accused included brokers who charged the immigrants for their services, using some of their money for the bribes.

''This is a corruption case based on the simple concept of greenbacks for green cards,'' said Louis D. Schiliro, assistant director of the F.B.I. in charge of the New York office, which investigated the scheme for about a year, using wiretaps and I.N.S. employees who worked undercover.

Edward J. McElroy, district director of the immigration service in Manhattan, said this was the largest number of I.N.S. employees arrested in such a scheme in New York, although similar schemes have been uncovered in Manhattan and elsewhere in recent years.

The Commissioner of the I.N.S., Doris M. Meissner, acknowledged in an interview in 1994, shortly after taking office, that the agency's low pay, antiquated computer systems, and broad power over immigrants' lives set up the potential for abuse by dishonest employees. There was ''a climate for abuse'' that did not exist in other agencies, she said.

Mary Jo White, the United States Attorney in Manhattan, who announced the charges, said that in exchange for the bribes, one immigration employee removed an applicant's criminal record from the official file. In other cases, she said, officers agreed not to verify claims made by applicants seeking to qualify for green cards, including whether their marriages to American citizens were legitimate or not.

The bribes averaged about $1,000, and ranged from $300 to $12,000, Ms. White said. The salaries of the accused immigration workers were $25,000 to $50,000 a year, she said.

It was unclear yesterday how many of the immigrants knew that bribes were being paid for them, or how many of them would have legally qualified for residency status. Ms. White said that the investigation was continuing. Officials did not say yesterday whether they would charge any of the immigrants or seek to deport them.

Prosecutors also described the murky world of immigration brokers in New York, and the indictment noted that at least three of them operated out of travel agencies.

An error has occurred. Please try again later.

You are already subscribed to this email.

The brokers even arranged sham marriages to secure eligibility for green cards, Ms. White said, and used code words like ''skirts'' and ''pants'' to refer to the men and women involved. In January, one man in a sham marriage called his broker to ask for the name of his ''wife,'' the indictment said.

Yesterday, 23 defendants were arrested and taken to Federal District Court in Manhattan on charges including conspiracy, bribery, and immigration fraud. Two of the immigration employees named in the indictment, which was unsealed yesterday, had pleaded guilty earlier, officials said, while five defendants had not yet been taken into custody.

One broker, Maria Diaz, who operated out of Gemma Travel in the Bronx, was accused of paying about $60,000 in bribes on nine separate occasions, officials said.

Ms. Diaz did not return a phone call seeking comment early in the day. In court, she did not make bail and could not be reached.

The indictment also charged an immigration lawyer, Francois Au of Manhattan, with bribery. Mr. Au, who was released on bond, did not return a call for comment.

Nelson A. Boxer, an assistant United States attorney, said that some of the brokers were overheard on wiretaps making threats about an immigration employee whom they believed was cooperating with Federal investigators.

Mr. McElroy said the case began after co-workers reported suspicious activity at the agency -- people coming in without appointments, being bumped ahead of other applicants and other irregularities.

Officials said that yesterday's case was not connected to one in 1995 in which four immigration clerks in the Manhattan office were charged with taking hundreds of thousands of dollars in bribes to issue employment authorization cards to thousands of illegal immigrants.

Some time earlier, eight employees of the Washington district office were convicted in a scheme to accept bribes to sell legal residency to 1,000 immigrants who did qualify and to give another 4,000 people permission to work, according to news reports.

Yesterday, a spokesman for Ms. Meissner, Eric C. Andrus, said the agency was continuing to improve internal auditing and computer systems to prevent such abuse. He said the fact that co-workers had made the initial reports showed that ''progress is being made and recognized within our own work force.''